Data storage devices store digital information on a rotating disc. Heads are coupled to an actuator assembly which is energized to position the head relative to the disc surface for read/write operations. The head includes transducer elements which are supported on an air bearing slider to read data from or write data to the disc. For operation, rotation of the disc creates an air flow along the air bearing of the slider to create a hydrodynamic lifting force. The hydrodynamic lifting force is countered by a load force at a load point so that the slider pitches and rolls above the disc surface at a fly height defined in part by the hydrodynamic lifting force of the air bearing and the load force supplied by a suspension assembly.
Areal density is increasing, necessitating a decrease in fly height parameters or head-disc spacing to increase bits per inch. As the head-disc spacing is decreased, shorter wavelength low amplitude disc roughness becomes more of a problem. As the wavelength of the surface roughness of the disc which the slider is required to follow decreases below the length of the slider it is more difficult for the slider to follow the topography of the disc surface increasing the propensity for head disc contact. Embodiments of the present invention provide solutions to these and other problems, and offer other advantages over the prior art.